Marine motor



Dec. 6, 1932. H. L. JOHNSON ET AL MARINE MOTOR Filed Sept. 7, 1929 2 Sheets-Sheet l Dec. 6, 1932. H. l., JOHNSON :a1-ALA MARINE MOTOR Filed Sept. '7, 1929 fill/67%@ L. I0/272507Z,

Harr

Loza

5 J LTO/272507Z,

Patented Dec. 6, 1932 UNITED STATES PATENT OFFICE HARRY L. JOHNSON, OF WAUKEGAN, ILLINOIS, AND LOUIS J'. JOHNSON, OF SOUTH BEND, INDIANA, ASSIGNORS TO JOHN SON BROTHERS ENGINEERINGCORPORATION, F SOUTH BEND, INDIANA, A CORPORATION 0F INDIANA MARINE MOTOR Application led September 7, 1929. Serial No. 391,028.

This invention relates in general to marine motors and more particularly to an outboard motor having a twin two-cycle engine with an attached muiier and a single tube for discharging the engine exhaustf under water and for conveying cooling water to and from the engine and mufiier cooling jackets due to the pressure and suction produced by the propeller.

1o Among the objects of the invention are: to combine a fuel distribution valve with the engine crank and to locate it in the crankcase: to shorten the fuel passages: to provide a single rotary valve for distributing fuel to a plurality of chambers: to directly connect a muier to a plurality of cylinders producing a smooth continuous outer surface: to provide connected water circulation passages for the cylinder and muier water cooling jackets which are short and direct eliminating pipes and fittings: to position twin cylinders rearwardly one above the other: to provide cooperating oil circulation passages in the crankcasing to eliminate piping: to automatically vary resistance to the exhaust by providing an auxiliary exhaust relief valve: to provide a signal for indicating that the cooling water is properly circulating: and in general, to produce the structure shown and described.

In the drawings illustrated a preferred embodiment of the invention, Fig; 1 is an elevation mostly in section illustrating an outboard motor embodying our invention: Figs.

2, 3, and 4 are sections taken on the lines 2 2, 3 3, and 4, repectively, of Fig. 1: Fig. 5 is a section on the line 5 5 of Fig. 3: Fig. 6 is a section taken on the line 6 6 of Fig. 1: Figs. Tand 8 are cross sections taken on the lines 7 7 and 8 8 respectively of Fig. 6, showing the exhaust and water passages: and Fig. 9 is a sectional view of the fuel distribution valve and its passages.

Referring more particularly to the drawings, this invention relates in general to the conventional type of outboard or inboard motor having a combustion engine power head with a nested fly wheel magneto 1,

a fuel tank 2 and the ordinary spark control lever, and carburetor which lare not shown in the present drawings.

The power head comprises a combustion engine with twin cylinders 3 and 4 arranged. one above the other and having a common water jacket 5. A crankshaft 6 is rotated 55 in a crankcase 7 common to the two cylinders having pistons 8 movable in the cylinders and connected to the crankshaft by piston rods 9.

Between the piston rod connections on the crankshaft is a cylindrical valve member 10 60 p fitting closel in a formed portion 11 of the crankcasing (see Figs. 1 and 9) which has a tubular inlet 12 from the carburetor with an inlet passage 13 extending partially around the casing 7 to provide a partially continuing `6&5 connection with the peripheral ends of valve passages 14 and 15 which extend from opposite sides of the periphery of the valve member 10 to the opposite faces thereof, thus forming a partition dividing the crankcasing into chambers and a distributor for admitting fuel from the carburetor and passage 13 t6 the different crankcase chambers alternately for a portion of the travel of the valve member l0 as it is rotated with the crankshaft, and u cutting ofi' each chamber from the admission of fuel when the other chamber is receiving it. Each of the engine cylinders as shown in Fig.

6 has a fuel passage 16 leading from its crankcase chamber to the explosion chamber with a back-fire prevention screen 17 located therein and in the opposite side of the cylinder is an exhaust passage 18 leading directly into a common muflier 19 for the two cylinders g5 which has a water jacket 20 communicating directly and continuously with the water jacket 5 of the cylinders, so that in effect they are a part of the same water jacket and the exterior surfaces of the cylinders and muffler are smooth and continuous presenting a neat and unitary appearance.

At the bottom of the muffler 19 as shown more clearly in Fig. 7 is a separate casting or an extension having a discharge passage 21 for conveying away the exhaust gases and this passage is located in the direct path of any condensation of liquid fuel or exhaust gases from the upper cylinder to the lower cylinder, so that instead of passing to the exhaust passage 18 of the lower cylinder these materials will be ejected through the discharge passage 21. i A partition 22 is also positioned between the exhaust ports of the two cylinders, with an extension 22a in the muffler casting, to prevent any liquid fuel in exhaust from passing directly from the upper cylinder to the lower cylinder, the edge of the extension 22a overlying the passage 21, thereby helping to insure that such discharge is through the mufier passage 21. K

Connected to the lower end of the crankshaft is a'drive. shaft 23 loosely contained in a passage 24 of a tubular casing 25 supporting at its lower end a stream-lined under water unit 26 in which is rotatablyinounted a propeller 27 connected by suitable gearing 28 with the drive shaft. In this casing 25- and the lower unit 26 are water inlet and outlet passages 29 and 30 terminating below an anticavitation plate 31 formed integral with the outer surface of the housing unit 26, the passages opening at the rear and in front of the upper path of travel of the propell-erblades so that the water therefrom will cause a pressure and exhaust circulation of cooling water for the engine and muffler jacket. Also formed in the tubular casing 21 and in the lower casing unit 26 is an exhaust passage 32 which terminates below the anti-cavitation plate 31 and at the rear of the plate behind the propeller to receive the suction effect of the latter.

In the tubular casing 25, the exhaustpassage 32 is divided as shown more clearly in Figs. 3 and 4 and the water inlet and outlet passages are at the rear and front of the casing respectively. At the top of the casing 25 is a housing 33 connecting the opposite eX- haust passages and providing a port 34 (see Fig. 2) to which the discharge passage 21 of the muliler is connected, as shown more clearly in Fig. 6.

The upper en d of the water inlet passage 29 is connected by passages 35 in the crankcase with the lower end of the unitary water Jacket surrounding the engine cylinder and mutllerand the water rises therein, as indicated by the arrows in Fig. 8 until it reaches a discharge port 36 above the upper cylinder 3 communicating with a water discharge 37 extending downwardly adjacent the engine discharge ports 18, as shown in Figs. 6 and 8 and terminating in a discharge passage 38 in the erankcasing, as shown in Fig. 1 which communicates with the upper end of the water discharge passage 30 in the tubular casing 25.

Oiling of this motor is effected by mixing the oil with the fuel, the surplus oil in the crankcase being thrown outwardly by the cranks and forced by pressure and suction through oil passages 39 in the crankcase and by a groove 40 in the crankshaft bearing and a connected oil passage 41 in the cylindrical erankcasing to discharge oil at the upper side of the interior of cylinder 3. Another oil passajge 42 extends from the bottom of the lower cylinder 4 to the lower crankshaft bearing 43 from which the oil may pass downwardly on the shaft 23 lubricating the lower bearings and connections thereof in a well known manner.

To mount the motor for swinging movement, an attachment bracket 44 having lower slotted guides 45 is pivotcd at its upper end to a split sleeve 46 embracing the upper portion of the casing 25 which allows the casing to turn freely in both directions for steering and reversing the movement of a boat. A thrust plate 47 is adjustably mounted in the guides 45 for engaging the casing 25 during the forward movement of a boat and a reverse lock consisting of upper and lower projecting ledges 48 and 49 are adapted to engage the thrust plate 47 when the motor is turned for reversing the direction of propulsion of aboat to which the motor is attached.

A steering handle is pivited to a frame 61 attached to the power head and having a stop 62 for engaging the handle, in one direction ofL movement. For remote steering a pulley 63 may be attachedas by clamping it between the crankcase 7 and the casing 25, to receive tiller ropes (not shown) which are connected in a well known manner to al front or remote steering gear. y

In starting a motor of this type exhaust back pressure is objectionable and although a manual pressure relief maybe provided, an automatic pressure relief actuated by the cooling water is attached to the tubular casing 25 below the-supporting sleeve 46 where it will not engageV the supporting bracket 44 and interfere with the complete rotation of the motor. This pressure relief is in the form of a valve having a easing 50 attached to the side of the casing 25 with a passage 51 at the top communicatlng directly with one side of the exhaust passage 32 and with a. passage 52 at the bottom communicating with the water inlet passage 29. Movable in the valve casing is a weightedv valve member 53 having a bevelled upper surface 54 to engage and close the lower end of a reduced passage 55 in the upper end of the valve. J ust below-the reduced portion of the valve are exterior openings 56 through which the exhaust may escape at the top of the valve member when it is in a lowered position. At the bottom of the valve member is a projection 57 on an engaging nut 58 threaded at the bottom of the valve casing 50 andfor holding the'valve above the water inlet passage 52 so that the pressure of water in the inlet passage 29 will raise the valve closing the openings 56 against the escape of the exhaust gases when the water has attained a predetermined pressure in the passage 29. c This device also acts as a signal for indicating the failure of the water circulation whenever the valve opens the exhaust to the atmosphere either in starting or in operation showing that some operative attention must be given to the motor or to the water cooling system thereof.

In operation this motor may be freely turned in either direction for steering and reversely moving a boat, the rotation of the propeller causing a circulation of cooling water through the combined engine and muflier water jackets. The fuel is distributed by a rotary valve mounted on the crankshaft in the crankcase; the exhaust from the muffler is discharged in the propeller race, and in starting is automatically discharged above water level bv a cutout operated by a predetermined pressure of the cooling water; and the fuel and water passages are short and direct, included in the casing parts, and free from pipes and fittings.

We claim:

l. An internal combustion engine of the two cycle two cylinder type having a closed crank case forpartially compressing the fuel, a crankshaft rotatable lin the crank casing, and a rotary valve more than twice the diameter of the crank shaft mounted on the crankshaft forming a partition dividing the casing into separate chambers and having ports -communicating with the interior and exterior of the crank case for controlling the admission of fuel to the crank case as the crankshaft is rotated.

2. A two cycle two cylinder internal combustion engine having a closed crank case and a crankshaft rotatable therein, and a rotary valve more than twice the diameter of and in connection with the crankshaft forming a partition dividing the crankcase into two chambers and having a fuel admission passage communicating with the interior and exterior of th-e casing for admitting fuel to each chamber of the crank case under suction created therein, the valve being rotated and controlled entirely by the movement of the crankshaft.

3. A rotary valve structure for twin com bustion engines having a common crank casing, comprising a rotary valve member mounted upon the crankshaft between the engines and dividing the crank casing into separate chambers, the rotary valve member having passages from the periphery thereof extending through opposite. faces and the k crank case having an admission port extending partially around the valve member and communicating with the peripheral openings thereof during a portion of the rotary movement of the valve member.

4. A combustion engine having cylinders with a common crank casing and a crankshaft rotatable therein, a circular valve member on the crankshaft dividing the casing into separate chambers and having passages from the periphery thereof to the opposite faces of the circular valve member, the crank case having a fuel admission opening communieating with the peripheral ends of the valve passages and the opening extending partially about the periphery of the valve member.

5. A rotary valve structure for multiple cylinder two-cycle combustion engines comprising a crankease, a crankshaft rotatable therein, a valve member of more than twice the diameter of the crankshaft mounted upon the crankshaft and forming a partition between the two crank case chambers, andF means in the valve member comprising passages from the periphery to opposite sides of the disc independent of the crankshaft which distribute the charge alternately to opposite sides thereof independent of the crankshaft.

6. A multiple cylinder combustion engine of the two-cycle type having pairs of crankcases and a crankshaft rotating therein, said shaft having a central section more than twice the diameter of the shaft fitting closely in and forming a common wall between the crankcases and having fuel passages extending fromthe periphery to opposite sides of the enlarged section independent of 'the crankshaft.

7. A multiple cylinder combustion engine of the two-cycle type having pairs of crankcases, and a crankshaft rotating therein, said shaft having an enlarged central section more than twice the diameter of the shaft. forming a partition between the crankcases,

and said section having passages forming charge admission valves from the exterior of the casing to the mterior of the crankcases independent of the crankshaft.

8. A two cylinder combustion engine having a crankshaft rotatable in the crankcase, and a rotary fuel valve for the engine carried by the crank shaft and considerably larger in diameter than the shaft forming a partition in the crankcase dividing it into separate chambers and having separate fuel admission passages leading from the periphery to opposite sides of the partition adjacent the center and free from the crank.

9. A rotary valve for two cylinder combustion engines comprising an engine crankshaft with an enlarged circular portion thereon to form a crankcase partition and having fuel distribution passages for controlling the fuel admitted to the separate chambers of the crankcase at the sides of the enlarged portion and independent of the crankshaft.

10. A two cycle combustion engine having tWo cylinders, a common orankcase, a crankshaft rotatable therein, and a valve mounted upon and rotatablewiththe crankshaft comprising a circular disc of relatively large size to form a partition in the crankcasing and having ports therein extending from the periphery to both sides of the partition and free from obstruction by the crankshaft at either side yfor controlling the admission of fuel to the crankcase.

HARRY L. JOHNSON. LOUIS J. JOHNSON. 

